Merge pull request #2889 from sharwell/fix-missing-select

Fix handling of missing 'select' clause

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers.CodeFixes/ReadabilityRules/SA1103CodeFixProvider.cs

@@ -153,7 +153,11 @@ private static ImmutableArray<SyntaxNode> CreateQueryNodeList(QueryExpressionSyn
         private static void ProcessQueryBody(QueryBodySyntax body, List<SyntaxNode> queryNodes)
         {
             queryNodes.AddRange(body.Clauses);
-            queryNodes.Add(body.SelectOrGroup);
+
+            if (!body.SelectOrGroup.IsMissing)
+            {
+                queryNodes.Add(body.SelectOrGroup);
+            }
 
             if (body.Continuation != null)
             {

StyleCop.Analyzers/StyleCop.Analyzers.Test/ReadabilityRules/SA1103UnitTests.cs

@@ -5,9 +5,9 @@ namespace StyleCop.Analyzers.Test.ReadabilityRules
 {
     using System.Threading;
     using System.Threading.Tasks;
+    using Microsoft.CodeAnalysis;
     using Microsoft.CodeAnalysis.Testing;
     using StyleCop.Analyzers.ReadabilityRules;
-    using TestHelper;
     using Xunit;
     using static StyleCop.Analyzers.Test.Verifiers.StyleCopCodeFixVerifier<
         StyleCop.Analyzers.ReadabilityRules.SA110xQueryClauses,
@@ -365,5 +365,91 @@ public void TestMethod()
 
             await VerifyCSharpFixAsync(testCode, expectedDiagnostics, fixedTestCode, CancellationToken.None).ConfigureAwait(false);
         }
+
+        [Fact]
+        [WorkItem(2888, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/2888")]
+        public async Task TestQueryExpressionWithMissingSelectAsync()
+        {
+            var testCode = @"namespace TestNamespace
+{
+    using System.Linq;
+
+    public class TestClass
+    {
+        private int[] testArray = { 1, 2, 3, 4, 5 };
+
+        public void TestMethod()
+        {
+            var x = from element in testArray
+                    where element > 1;
+        }
+    }
+}
+";
+
+            var expectedDiagnostics = new DiagnosticResult("CS0742", DiagnosticSeverity.Error).WithLocation(12, 38).WithMessage("A query body must end with a select clause or a group clause");
+            await VerifyCSharpFixAsync(testCode, expectedDiagnostics, testCode, CancellationToken.None).ConfigureAwait(false);
+        }
+
+        [Fact]
+        [WorkItem(2888, "https://github.com/DotNetAnalyzers/StyleCopAnalyzers/issues/2888")]
+        public async Task TestQueryExpressionWithMissingSelect2Async()
+        {
+            var testCode = @"namespace TestNamespace
+{
+    using System.Linq;
+
+    public class TestClass
+    {
+        private int[] testArray = { 1, 2, 3, 4, 5 };
+
+        public void TestMethod()
+        {
+            var x = from element in testArray where element < 3
+                    where element > 1;
+        }
+    }
+}
+";
+            var fixedTestCode = @"namespace TestNamespace
+{
+    using System.Linq;
+
+    public class TestClass
+    {
+        private int[] testArray = { 1, 2, 3, 4, 5 };
+
+        public void TestMethod()
+        {
+            var x = from element in testArray
+                where element < 3
+                    where element > 1;
+        }
+    }
+}
+";
+
+            await new CSharpTest
+            {
+                TestState =
+                {
+                    Sources = { testCode },
+                    ExpectedDiagnostics =
+                    {
+                        Diagnostic(SA110xQueryClauses.SA1103Descriptor).WithLocation(11, 21),
+                        new DiagnosticResult("CS0742", DiagnosticSeverity.Error).WithLocation(12, 38).WithMessage("A query body must end with a select clause or a group clause"),
+                    },
+                },
+                FixedState =
+                {
+                    Sources = { fixedTestCode },
+                    ExpectedDiagnostics =
+                    {
+                        new DiagnosticResult("CS0742", DiagnosticSeverity.Error).WithLocation(13, 38).WithMessage("A query body must end with a select clause or a group clause"),
+                    },
+                },
+                CodeFixIndex = 1,
+            }.RunAsync(CancellationToken.None).ConfigureAwait(false);
+        }
     }
 }

StyleCop.Analyzers/StyleCop.Analyzers/ReadabilityRules/SA110xQueryClauses.cs

@@ -218,7 +218,11 @@ private static void HandleSelectOrGroup(SelectOrGroupClauseSyntax selectOrGroup,
             {
             case SyntaxKind.SelectClause:
                 var selectClause = (SelectClauseSyntax)selectOrGroup;
-                tokensToCheck.Add(selectClause.SelectKeyword);
+                if (!selectClause.IsMissing)
+                {
+                    tokensToCheck.Add(selectClause.SelectKeyword);
+                }
+
                 break;
             case SyntaxKind.GroupClause:
                 var groupClause = (GroupClauseSyntax)selectOrGroup;